Regulatory T cells (Tregs) play an essential role during homeostasis and tolerance of the immune system. Based on our previous study that exposure of pregnant rats to staphylococcal enterotoxin B (SEB) can alter the percentage of CD4/CD8 subsets in the thymus of the offspring, in this study, we focus on the influence of exposure of pregnant rats to SEB on number, function and response of Tregs in the thymus of the offspring. Pregnant rats at gestational day of 16 were intravenously injected with 15 μg SEB and the thymuses of the neonatal and adult offspring were harvested for this study. We found that exposure of pregnant rats to SEB could significantly increase the absolute number of Tregs and the FoxP3 expression level in the thymus of not only neonatal but also adult offspring. Re-exposure of adult offspring to SEB remarkably reduced the suppressive capacity of Tregs to CD4+ T cells and the expression levels of TGF-β and IL-10 in the thymus, but had no effect on production of IL-4 and IFN-γ. Furthermore, it also notedly decreased the absolute number of Tregs and the FoxP3 expression level. These data suggest that prenatal exposure of pregnant rats to SEB attenuates the response of increased Tregs to re-exposure to SEB in the thymus of adult offspring.

中文翻译：

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怀孕大鼠暴露于葡萄球菌肠毒素B会减弱成年后代胸腺中增加的Treg对SEB再暴露的反应。

调节性T细胞（Tregs）在体内平衡和免疫系统耐受中起着至关重要的作用。根据我们之前的研究，即怀孕大鼠暴露于葡萄球菌肠毒素B（SEB）可以改变后代胸腺CD4 / CD8亚群的百分比，在这项研究中，我们集中于怀孕大鼠暴露于SEB的影响后代胸腺中Tregs的数量，功能和反应。妊娠第16天的妊娠大鼠静脉注射15μgSEB，并收集新生儿和成年后代的胸腺进行此项研究。我们发现，妊娠大鼠暴露于SEB不仅会显着增加新生婴儿的胸腺中Treg的绝对数量，而且FoxP3表达水平也会增加。成年后代再次暴露于SEB会显着降低Treg对CD4 + T细胞的抑制能力以及胸腺中TGF-β和IL-10的表达水平，但对IL-4和IFN-γ的产生没有影响。此外，它还明显降低了Treg的绝对数目和FoxP3表达水平。这些数据表明，成年大鼠胸腺中妊娠大鼠的产前暴露会减弱Tregs对再暴露于SEB的反应。